Question: Rewrite as a simplified fraction. ${0.2\overline{1} = {?}}$
Explanation: Let $x$ equal the decimal. Set up two equations such that the digits after the decimal point are identical. ${\begin{align*}100x &= 21.1111...\\ 10x &= 2.1111...\end{align*}}$ Subtracting the two equations, we have: ${90x = 19}$ ${x = \dfrac{19}{90}} $